Professional golf tournaments -- at least those played at the highest level of the sport -- are typically 72 holes, meaning four rounds of golf. These 72-hole, four-round events are usually played Thursday, Friday, Saturday and Sunday.
But how did it become standard practice that a 72-hole golf tournament would be played on these four days of the week?
Turns out, the answer is the Masters Tournament.
Before the Masters Tournament came along, golf tournaments were not spread out over four days. Once 72-hole golf tournaments became the standard for championship golf, the 72 holes were spread out over two or three days.
The US Open used to be played over two days, with 36 holes played per day. In the event of a playoff, a 36-hole playoff would be conducted the next day, making for three brutal days in a row.
The PGA Championship was a match-play affair up until 1958. That tournament took up a whole week. There was 36 holes of stroke-play qualifying, followed by the Round of 64 and the Round of 32 on Wednesday in 18-hole matches. Then, one 36-hole match round was played per day for the next five days. However, that wasn't always on a Monday through Sunday schedule.
It was the folks at Augusta National Golf Club who came up with the four-day, 72-hole schedule that ran Thursday through Sunday. The reason tournaments previously ran three days and ended on Saturday was the existence of Blue Laws in large portions of the country, forbidding certainly businesses and activities on Sunday.
Bobby Jones decided it was better to have the event played out over four days, and Augusta National co-founder Clifford Roberts agreed, liking that it helped players who struggled in the back end of a 36-hole finale. The idea was to have other events spaced out over the course of the tournament other than just the golf itself. The club could also sell tickets to four days of tournament golf. Having special events in the pre-tournament days would drive in fans to watch the whole week.
The US Open went to a Thursday through Sunday schedule in 1965, the year after Ken Venturi won at Congressional Country Club on a 36-hole Saturday in which he nearly died for heat exhaustion. The Open Championship went to four days in 1966.
Ultimately, every major professional golf tour in the world adopted this schedule, and that's why golf tournaments are played Thursday through Sunday.